[old_tv_nut]

You would have to get the spec sheets for the special version and matching reversal print film. It's possible that the taking film was low contrast, with the wide latitude of a negative, so it could be printed on high contrast reversal print material with a range of exposure adjustment.

At one time, Kodak produced a special low contrast 35mm print film for video use. The shadow density would be restored electronically. This gave better shadow detail than could be obtained with regular contrast film and the telecine cameras of the time, which had limited dynamic range in the shadows.

Edit: I also wonder who had a need for 35mm motion picture reversal film. Could it be that the 35mm version was not sold in movie rolls, and only used for slide (still) duplication?